Canadian Overseas Petroleum Ltd. (COPL) produced first oil production from the Frontier 1 sands in the Cole Creek Unit in Powder River basin, Converse County, Wyoming.
In the last week of December, the company started recompletion operations on well 11-27-35n-77w to evaluate the light oil potential of the Frontier 1 reservoir sands. The lowest of three Frontier 1 sands was perforated with 65 ft of perforations with no subsequent stimulation.
Initial fluid recoveries consisted of black heavy degraded oil, black emulsion, minor brown un-gasified light oil, and water. Fluid entry from the reservoir has remained constant while pumping at rates between 125-135 b/d. Gasified light oil volumes increased over the last week with increasing oil cuts up to 86% at week’s end, with the well slugging heavy black degraded oil, emulsion, and drilling mud periodically at higher water cuts (up to 85%).
The proportions of heavy black degraded oil, emulsion, and drilling mud are decreasing as the well continues to clean up from near well-bore damage caused by significant volumes of light freshwater drilling mud invasion during drilling 10.5 years ago. COPL has opted to continue with the current process of well clean up rather than a hydrocarbon-based stimulation to remove degraded oil and emulsion from the near well-bore area. A stimulation would remove damage but at a significant cost.
An “Oil Down To” elevation at the base of the Frontier 1 perforations has been determined at about 760 ft below the crestal elevation of the Cole Creek Anticline. The area within the “Oil Down To” elevation is about 8,000 acres with reservoir sand thickness ranging from 50-115 ft, thinning in the northern area.
About 50 ft of Frontier 1 sands remain unperforated in the 11-27 well. These sands will be completed when the perforated sands in 11-27 are hydraulically fractured as part of a stimulation campaign on the recompleted wells later this year.
The second well in the program, 4-27-35n-77w, lies about 0.5 miles northwest of 11-27 with reservoir sands 230 ft higher in elevation. The lower Frontier 1 sand will be perforated with 56 ft of perforations. In common with 11-27, no stimulation of the perforations is planned. Reservoir quality from wire-line logs from 4-27 well appears to be better than the reservoir perforated at 11-27. Operations will commence when services required become available.
COPL has 100% interest in the Cole Creek Unit.